Home > CUCM, Gateways > Forcing Cisco IP Phones into SRST mode

Forcing Cisco IP Phones into SRST mode

Hi All

Have you ever wanted to know how to force your remote site Cisco IP Phones into SRST mode without turning off the CUCM servers or shutting down your WAN link. This can be achieved by using a access list on the router/WAN interface

Configure the access list that blocks the following

SIP: 5060 (TCP/UDP),
Secure SIP: 5061 (TCP/UDP),
SCCP: 2000 (TCP)
Secure SCCP: 2443 (TCP)
Standard RTP Ports: 16384-32767 (UDP)

ip access-list extended ACL-VOIP-CONTROL
deny tcp any any eq 5060
deny udp any any eq 5060
deny tcp any any eq 5061
deny udp any any eq 5061
deny tcp any any eq 2000
deny tcp any any eq 2443
deny udp any any range 16384 32767
permit ip any any

Apply the access control list to the WAN interface to which the administrator wishes to block voice traffic.

interface X/X
ip access-group ACL-VOIP-CONTROL in

The phones will now failover into SRST mode

Enjoy

The Voice Man

Advertisements
Categories: CUCM, Gateways
  1. No comments yet.
  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: